Let F be the magnitude of the frictional force. This force performs an amount of work W on the bullet such that
W = -Fx
where x is the distance over which F is acting. This is the only force acting on the bullet as it penetrates the tree. The work-energy theorem says the total work performed on a body is equal to the change in that body's kinetic energy, so we have
W = ∆K
-Fx = 0 - 1/2 mv²
where m is the body's mass and v is its speed.
Solve for F and plug in the given information:
F = mv²/(2x)
F = (0.00426 kg) (881 m/s)² / (2 (0.0444 m))
F = 37,234.8 N ≈ 37.2 kN
Explanation:
The liquid contains only one element. -The liquid is a pure substance. The number at the end of an isotope's name is the -mass number. While looking at xenon (Xe) on the periodic table, a student needs to find an element with a smaller atomic mass in the same group.
Answer:
the liquid has less height than the mercury
h_{ liquid} = 
Explanation:
The pressure as a function of the height is given by
P = ρ g h
where ρ is the density of the liquid, g the acceleration of gravity and h the height reached by the column of the liquid
In that case they say that the pressure is the standard one that is P = 1.01 10⁵ Pa = 760 mmHg
The first way to give the pressure is in SI units and the second way is the height that the mercury column reaches
In the case of building a barometer with a liquid that has a density greater than that of mercury
ρ_liquid > ρ_Hg
the pressure
P =ρ_lquid g h_liquid
if we have the same pressure
ρ_{Hg} g h_{Hg} = ρ_{liquid} g h_{liquid}
h_{ liquid} =
therefore the liquid has less height than the mercury
(a) For the work-energy theorem, the work done to lift the can of paint is equal to the gravitational potential energy gained by it, therefore it is equal to

where m=3.4 kg is the mass of the can, g=9.81 m/s^2 is the gravitational acceleration and
is the variation of height. Substituting the numbers into the formula, we find

(b) In this case, the work done is zero. In fact, we know from its definition that the work done on an object is equal to the product between the force applied F and the displacement:

However, in this case there is no displacement, so d=0 and W=0, therefore the work done to hold the can stationary is zero.
(c) In this case, the work done is negative, because the work to lower the can back to the ground is done by the force of gravity, which pushes downward. Its value is given by the same formula used in part (a):

Answer:
49 kg is the mass of the couch.
Explanation:
GPE = mgh
9800 = m * 10 * 20
9800 = 200m
m = (9800/20) = 49 m
Thenks and mark me brainliest :))